critical

SessionNotCreatedException: Could not start a new session

WebDriver could not create a new browser session. Usually caused by a version mismatch between the browser and the driver.

Common Causes

  1. 1ChromeDriver version doesn't match Chrome browser version
  2. 2Browser is not installed
  3. 3Driver binary is not in PATH
  4. 4Another browser instance is using the same profile
  5. 5Insufficient system resources

How to Fix

Use webdriver-manager to auto-manage drivers

# Install
pip install webdriver-manager

# Python
from selenium import webdriver
from selenium.webdriver.chrome.service import Service
from webdriver_manager.chrome import ChromeDriverManager

driver = webdriver.Chrome(
    service=Service(ChromeDriverManager().install())
)

webdriver-manager automatically downloads the correct driver version for your browser.

How ObserveOne Helps

ObserveOne manages browser and driver versions in CI/CD environments, preventing version mismatch failures.

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